Many electronic systems, such as computers and cellular phones, often include a counter to generate counter values. The system may use the counter values for various purposes. For example, the counter values may be used as identification numbers, version numbers, or other kinds of reference values associated with certain information in the system.
Some conventional counters may employ a relatively large number of programmable fuses to store a corresponding large number of counter values. Such a large number of programmable fuses may reduce space in these systems. Further, in some systems, the counter values may play some key roles in the system security. Thus, if the counter values in the system are improperly protected, system security may be compromised,